Cactus care - help please?

[Basilsweetheart27]

Hi, I'm new here waves. I need some advice please. I have got two cacti, one I bought from a garden centre and one I was given.

I'm not sure how often to water them - my neighbour told me to just keep their soil damp, but a gardening website told me to only water them every two weeks. It also said to feed them every two weeks throughout the growing season. Their soil is currently quite dry, and it's a week til they need watering. I have killed a poor cactus by over watering before, so I'm a bit wary of over doing it, but I don't want these two to die of thirst.

Anyone out there know how much/how little I should water them please? They live on a South facing windowsill. thanks in advance.

Definitely don’t keep them damp!! Most cacti live in the desert or other pretty arid environments so are used to dry soil and then quick bursts of rain. I water mine every week or two depending on how hot it is (the worst thing for a cactus is to be cold and damp so the cooler the conditions, the less water they will want). It’s absolutely fine for the soil to dry out between watering, unless it’s a Christmas cactus.

They also go dormant in winter so unless they’re above a radiator(in which case, move them!) reduce watering right down once the weather turns cool in autumn.

I've had mine for a couple of years, I'm by no means an expert but they thrive with neglect I've found! I barely water them at all, they're on a shelf in a light room (kitchen) with no direct sun and dry out between every watering because I forget they're there, although I'd imagine they'd do fine wherever. Definitely don't keep damp, they store water so don't need excess. Mine gave me a purple flower this year, didn't even know they could do that at the time.

Cacti have evolved to survive in very arid habitats - their bodies are basically water storage organs, so that they can survive long periods without water.
Virtually all cacti and succulents sold in garden centres are potted in highly unsuitable potting mixes (often very peaty ones - they are imported from Dutch and Belgian growers who grow them in their millions). Therefore, it's usually good practice to repot them into a very well drained mix of John Innes 2 or 3, with extra grit - about 50/50, but I would understand if you don't feel confident to do this.
During the summer months they should be watered well, then left to dry completely before the next watering, which means there is no cut and dried period, it depends how long they take to dry out.
They also require as much sun as you can give them, i.e. On your sunniest windowsill.
They should go into dormancy between October and March when they can be left completely dry unless grown in a warm room.
In short, benign neglect seems to suit them well.
I have grown cacti and succulents for over 40 years, and have two large greenhouses full of them!
A photo would help too, as people often confuse cacti with "other succulents", and treatment might differ depending on species.
(Sorry for the long waffle!)